Prostate Cancer Foundation-funded Genetic Study of Men of African Ancestry Finds New Risk Factors for Prostate Cancer

One in six Black men in the United States will be diagnosed with prostate cancer in his lifetime versus one in eight white men. Black men are more likely to be diagnosed at a younger age, with more aggressive disease, and are more than twice as likely to die of prostate cancer. New findings from Prostate Cancer Foundation (PCF)-funded investigators shed light on the genetic underpinnings of this racial disparity and point the way toward more effective screening strategies.

Studies have identified close to 270 genetic variants linked to prostate cancer risk, but genetic researchers have yet to explain the disproportionate risk among men of African ancestry. Nor have they been able to predict which Black men face a high risk for aggressive prostate cancer.

To address these questions, Christopher Haiman, ScD, director of the Center for Genetic Epidemiology at the Keck School of Medicine of USC and AFLAC Chair of Cancer Research at the USC Norris Comprehensive Cancer Center, led a meta-analysis of 10 genome-wide association studies pooling data representing more than 80,000 men of African ancestry (19,378 men with prostate cancer and 61,620 healthy controls) collected in the U.S., Africa and the Caribbean.

The researchers found nine previously undiscovered genetic variants that increased the risk for prostate cancer in men of African ancestry, seven of which are found either largely or exclusively in Black men. One new variant in the 8q24 region, long known to influence prostate cancer risk, is found only in men of African ancestry. This variant influences the risk of higher rates of aggressive disease among Black men, researchers concluded. They also showed that a multiancestry polygenic risk score was able to differentiate between the risks of developing aggressive and nonaggressive prostate cancer in men of African ancestry. Their study was published March 3 in the peer reviewed journal European Urology.

The newly identified variants can be used to refine polygenic risk scores, genetic tests that assess a person’s risk for developing a condition based on the combined influence of multiple genetic factors and can help patients decide how early and often to get screened.

“Addressing African American disparity in prostate cancer is a critical focus for the Prostate Cancer Foundation and we congratulate Dr. Haiman and colleagues on their findings which will lead to more effective precision screening strategies for men of African ancestry,” said PCF President and CEO Charles J. Ryan, MD. “Through the Robert F. Smith-PCF Special Challenge Award for the Smith Polygenic Risk Test, we are proud to invest in the vital work of Dr. Haiman and all of the RESPOND investigators to understand and address the reasons why Black men disproportionately experience aggressive prostate cancer.”

Haiman and collaborators study prostate cancer among Black men through the $26.5 million, multi-center RESPOND (Research on Prostate Cancer in African American Men: Defining the Roles of Genetics, Tumor Markers and Social Stress) study, funded by the PCF, the National Cancer Institute, and the National Institute on Minority Health and Health Disparities. This work is ongoing, including research into how social determinants, access to care, genetics, and tumor characteristics affect prostate cancer diagnosis, progression, recurrence and survival rates.

With funding support from PCF and Robert F. Smith, Haiman and colleagues also are working to develop the Smith Polygenic Risk Test for Prostate Cancer, a non-invasive, early detection test that will identify a man’s lifetime prostate cancer risk using a combination of the nearly 270 genetic variants obtained from a single sample of saliva or blood.

“The results of this research will markedly change the ways physicians test for prostate cancer. We now have the ability to identify at-risk men before they develop the disease and proactively implement the most effective preventive measures and treatments,” said Robert F. Smith, Founder, Chairman and CEO of Vista Equity Partners. “We must continue to make investments in health equity research and transform prostate cancer from a life-altering diagnosis into a manageable condition.”

Since its founding in 1993, PCF has invested over $30 million in health disparities research through 48 different research programs with more than 20 institutional collaborators.

This news first appeared on prnewswire.com.